Densitometer



Oct. 28, 1952 J; DoLzA 2,615,328

DENSITOMETER Y Filed Aug. 18, 1951 4 Sheetfs-Sheet 1 #YM/mfc .sf/evo 007HA v/NG A P/sToN Pggan JH/v DOL zA o? T Torah/Ens Oct. 28, 1952 J. DoLzADENSITOMETER Sheets-Sheet 2 Filed Augf 18, 1951 E W w A Oct. 28, 1952 J.DoLzA 2,615,328

DENSITOMETER Filed Aug. 18, 1951 4 snets-sheet s INVENToR. fof/M DoLzAOct. 28, 1952 JNVENTOR.

fof/M O04 z A -tation of the chamber. ysity greater than the density ofthe fuel move l Fig. 3 isa sectional view on line 3-3 of Fig..

Fig. 4 is a view in the direction of arrow 4 of Fig. 1 of a float guide.

Patented Oct. 28, l1952 eswPA'r DENsrroME'rER A.

John Dolza, Davisburg, Mich., assigner to' General Motors Corporation,Detroit, Mich.,` a corporation of Delaware Application August 18, 1951,serial No. 242,568

2 claims. (ci. 73,-32)

. 41 This invention relates to liquid density sensing apparatus ordenstometer; and its object is to y passagessl"(iig. 1o 1of the hub 26and thence obtain a mechanical movement indicative of the density of a.liquid which, for example, may be the fuelvused by an internalcombustion turbine.

This object isaccomplished in the' disclosed embodiment of the presentinvention by the use of floats of different densities all within therange of vthe density of the liquid. In the case of turbine fuel, thesedensities might -be in the range of .60 to .90. The liquid iscontinuously sampled yby causing it to pass through a rotatingdensitometer chamber within which the floats are supported for movementradially of axis of ro- The floats having denoutwardly and those havinglesser density move or remain inwardly. As fuel density increases oflower density is used to effect a mechanical Amovement which correspondsto the density of "the fuel.

Further objects and advantages of the present invention will beapparent. from the following description, reference being had toltheaccom-j'v panying drawings wherein a preferred embodiment of the presentinvention .is clearly shown. In the drawings: 1

from a minimum, the inward force of the floats Fig. 1 is a longitudinalsectional view'vof a I densitometer embodying the presentinvention.

Fig. 2 is a longitudinal sectional view of a float drawn .to a scalelarger than in Fig. 1.

Fig. 5 is a sectional view on line 5-5 of Figui, Fig. 6 is a fragmentarysectional view on line 6--6 of Fig.1.

Fig. 7 is a diagram showing vfloats in inner and outer positions. andthe surfaces of a reaction rplate which the floats respectively engage.

Fig. 8 is a diagram showing, in section, the fioat engaging surfaces ofthe reaction plate.

Fig. 9 is a View in the direction of arrow 9 of Fig. 1 of the reactionplate.

Fig. 10 is an enlarged sectional view on line A'Fig. 11 is an enlarged,fragmentary sectiona yview on line ll-I I of Fig. 9.

Referring to Fig. 1, a case supports bearings A2| and 2| a for a shaft22 having splines 23 for making 4connection with a driving shaft andhaving splines 24 connected with splines 25 of vthe hub 26 of a reactionplate 21 as shown also is such that complete ychanges .the desiredfrequency. i The screws-31 Secure to carriage 38 two rings Ainto lthespace enclosed by a housingv 32 whose flange 33 is attached'by-screws34, threaded into a ring 35, to a plate 36 which screws 31 attached toaoat carriage and guide 38 splinedly connected' to shaft22 and slidablethereon;v The 1h'ousing`32 has holes 39 for the exit of liquid from thehousing to the case 20 and thence Ythrough'a meteringor resistrictionorce 40'111 a block 4l supported by a bushing 42 which provides athreaded hole 43'A for'receiving a` liquid exit pipe. Due to centrifugalforce generated by the liquidk rotating with housing 32, the outletpressure is higher` than the inlet pressure. The out flow whic'hisregulated by the restriction-'40 of fuel occur at and 5l which togetherprovide spherical sockets vfor the ball ends52 `of hollow floats 53.Each vinvouter row-to represent fthe outermost positions of the'floatcaps. 1 There ar'e I4 oats=ar ranged as shownin Fig. 7 lin 7 pairs," thefioats of each pair .being diameterically-opposite.r The numbers I f tolfapplied to circles `in Fig. 7.'-in` dicatefthe, locations of the oats.The float capengaging surfaces or pads Yof plate 21 which respectivelyare engaged by thel caps of these floats are marked `Ip to' 1prespectively. The pads are separated by notches 65. Fig. 8 shows thateach pad is a segment of a` cylinder whose radius isrepresented byarrows R. -The centers of curvature of the pads Ip to 'Ip arerespectively located at centers l to 1 in Fig. 8. v v

v4If, for example, the liquid whosedensity is to be sensed lies in therange of .68 to .90, densities of the pairs of floats are preferably asfollows:

Specific Pairs of floats gravity' f To obtain these different specificgravities,the vportions of the floats between lines X and Y (Fig.

2) receive different amounts of chromium plating. Some of the plating atthe end of the caps 60 is buff'ed' off so that the distance betweenlines X and Zwill` be uniform.

The arrangement of the floats is such that loading of the shaft 22 issubstantially in balance'.4

Fig. 1 shows the status when the liquid inhousing 32 has density greaterthan the density' of' n -sutablef manner, .for example,r by aspring 14-at- /faGhBdto-a stud 14a and to a band 115 'attached i'lofthedisc 'itAby a screw 16. Y

thefliquid has density 'less than .the density -o'fjzoats Tf and,greater than theV density of; floats 'B'fioats 11j move'outwardly clearof pads 11T-while the other iioats remain in. Lift movement ofthe -oatcarrier and guide 38 is limited by engagement of 'floats' Bf with. pads6p. .Therefore disc t34 moves clockwise an' amount whichA represents thedensity of the liquid'. As the density' of' the liquid decreases', thepairs of floatsl moveA out in :succession until only floats lf remainin' to engage pads itpl 'Theangul'ar displacementsl clockwise of disc L3take place in= stepswhichrepresent .7 different indications ofliquidzspeciiic'gravity which, for' example, might -be .872,A i45'1-17,790,y -763l .T363 .1708; l

, VIn case yther liquidi density were lessl than the density of floatsIf those oatsialso'moye'outxand oat carriage 38 .moves left until vitengages reaction plate-"ll` This final' movement. 'of carriage 38provides n'o indicationl other than that the liquid. isi' tooV th'in'for' the use for which it was intended'.

As liquid` density increases fronia value below the useful minimum, 'thepairs of floats `|inove in sequentially, lf to 1f, to engage theirrespective pads Into-11i to eliect, in steps, counterclo'ckwise movementof Vdisc 13; The, inward force applied to those ypairs'. of floats"having density nearest 't`o butrlessthanthe density of the liquid issuiiicien't to. c'ausetherfloats moving inf t'o engage` their padsIndication of density may be obtained: by pro- "vid'i'n'g the' disc 13with a scale 1T movable adjacent a fixed pointer 182 If the densitometeris lfused to effect control over other apparatus, for

exarr'iple,` apparatus for controlling the' iiowof fuel toburners of aninternal combustion turbine jet engine, disc 'I3 provides a cam groove80 of suitable contour which receives a follower roller 8l carried by alever 82 pivoted at 83 and having an arm received by a notch 84 in avalve rod 85 which moves a. valve of an hydraulic servo 8B of the -t'ypein which a piston follows a valve to Whatever position the valve ismoved by its rod v8'5..4 The piston rod 81 connected4 with the pistonmoves according to movements of the rod 85.

YRod 851. caribe-:used to impart movements to fuelflow"controiapparatusinorder thatifuekflow'will Floats 'If are pressedagainst pads 1p by be controlled in accordance with fuel density as Wellas other parameters.

While the" embodiment' ofi the present invention as hereindisclosed,constitutes al preferred form, it is to be understood that other formsmight be adopted.

What is claimed is as follows: 1'. A liquid density sensing apparatuscompris- :aV driven shaft,y oats of different densities vina-range of'densities of the liquid whose density is' toi 'be sensed', a reactionplate having a hub fixed to the shaft and providing pads located in acircular row around the shaft and having surfaces tobe engaged,respectively by floats of different densities, said pad surfaces beinglocated,

Ilongitudinally ofl the shaft axis, atI different distances from theplate hub; a membersupported for movement coaxially of theshaf-t andoperar tively ,connected therewith, means provided-by the member forsupporting each iloa't for-,movement radially of the sha-ft axis fromy alocation in which i-t may eng-age i-.tsA particular' pad ofthe reactiveplate rwhen the' density of the float-isless than the density of theliquid to' a: location in which the: float clears the reaction` platewhen its density is greater than'the' density of the liquid, saidmovement taking place underthe irrfluence of centrifugal force when theshaft'v is rotated at relatively high speed,.meansl forurg'ing themember toward the plate, the distance-between the member andtheplate'depending-on which one of the iioats engages' a pad of; itheplate, means-'connected withv the shaft 'and pro.- viding a chamber'surroundingthe plate and iloats, said chamber containing the liquidwhose density is to belmeasured, and an elementoperatively connectedwith the float supportingrmember, the position of the element beingindicative ofthe density of thesliquid'. I 2. A liquid'. density sensingVapparatusz comprising a driven shafta housing, surrounding, the shaftand providing av chamber for' receiving liquid whose density is to besensed,x duct means for directing the liquid intoY the chambernear theshaft, outlet ducts providedl by theho'usin'g remote from' the shaft, areaction plate with .the housing and driven by the shaft, said reactionplateU providing pads having surfaces` to" be' engaged, respectively Vbyoa'ts of different densities, s aid pad surfaces being located atdiffereritfdis'- vtancesv from "a plane at right angles to the shaftaxis, a housing vsupport connectedwith the .shaft for sliding movementtherealongfloats` off different densitiesv in a range of'A densities'-of liquid passing through the chamber,v meansconnecting the floats withthe housing supporty and provid-- in'g for movement of each iioatradially of the shaft from a location in which it may engage. i'tsparticular pad of the reaction plate-'When the density of the float isless' than'the density of the liquid in the chamber toY a. location inwhich 'the float clears the reaction plate WhenI its density is greaterthan the density of the liquid the chamber, said movementtaking. placeunder the iniiuence of centrifugal force when the shaft is rotated atrelatively' high' speed, mea-nsf. for urging the floats towardthereactionf plate, whereby the position of the housing along theshaft'fi's determined in accordance`v with which on'e'ofvthe fioatsengages the reaction/plate and a movable member operatively connected`withY the housing the position of the member being indicative of thedensity ofthe liquid. v

JOHN DOLZIA. Nofreference cited. 1

